This invention relates to a turnstile system used to meter and control the passage of persons through a passageway, and, more particularly, to such a turnstile that provides a wide passageway while preventing unauthorized access.
Turnstile systems are placed at the entries and exits of many regulated areas to meter the movement of persons into and out of those areas. Most turnstile systems are used where each person must pay a fee to gain entry, the fee being in the form of cash, tokens, fee cards, or other payment medium. The turnstile remains locked against rotation to permit entry until the fee is paid, and then is unlocked so as to permit one (and only one) person to pass through. In many instances, such turnstile systems are bi-directional, permitting entrance by rotation in one direction after the fee is paid, and permitting exit by rotation in the opposite direction without payment of a fee. Bi-directional turnstile systems are most commonly found in rapid transit stations, although not all rapid transit turnstile systems use bidirectional turnstiles.
The turnstile meters the movement of persons into and out of the regulated area, but also serves as the primary line of defense against persons who seek to defeat the fee payment system and gain entry without payment. Although the number of persons who attempt to defeat the system is typically small, significant revenues may nonetheless be lost. The physical barrier of a turnstile deters most persons who would otherwise try walk to directly into the fee-paid area without paying the fee. However, others may attempt to gain entry by crawling under the turnstile, vaulting over the turnstile, squeezing past the end of the turnstile arm, or crowding two persons through with a single payment. Crawling under the turnstile and squeezing are preferred by some who would attempt to enter without paying, because their activity is less conspicuous than vaulting over the turnstile. The turnstile desirably serves to deter these other types of attempted entry without payment.
The design requirements for a turnstile therefore require a balance between convenience of use for those who pay, and creation of a barrier against entry to those who do not pay. Additionally, since many mass transit systems wish to permit persons to exit through the same turnstile system, such a turnstile must be reversible in its movement to permit persons to pass. There are often fire safety regulations requiring that there be at least a minimum permitted movement rate of persons from the restricted area through the turnstile in the event of an emergency. The turnstile system must be safe for those who pay and even for those who do not pay.
The design considerations involve, at least in part, decisions as to the layout and dimensions of the turnstile system. Convenience of use during entry for persons who pay, the required rate of exit flow in emergencies, and safety usually suggest a larger passageway through the turnstile, while creation of a barrier to unpaid entry suggests reduced passageway size to permit the passageway to be more fully blocked by the turnstile when payment is not made.
There is a continuing need for a turnstile that satisfies these various requirements, is rugged, and can be built and maintained economically. The present invention fulfills this need, and further provides related advantages.